What can give a bad first impression at a networking event?

This was the first question in the #u30pro chat this past week:Q1: As young professionals, what is one thing that can give a bad first impression at a networking event? #u30pro

Everyone had really good answers so I made a new Storify post here with everyone's answers from the questions.

Definitely read this post because there are some GREAT tips for networking at events... the Do's and the Don'ts.